Four-wheel drive model car

ABSTRACT

A miniature gasoline engine is installed at the rear section of the model car. A first transmission gear is connected to and driven by the axle of the miniature gasoline engine, which in turn engages a parallel, second transmission gear, which is mounted at an end of a first transmission axle. A first bevel gear is provided at the other end of the first transmission axle, which engages a perpendicular, second bevel gear. The second bevel gear is connected to a center differential located in the center of the model car which in turn drives a second transmission axle (i.e., the main transmission axle). The second transmission axle runs through the center differential and axially through the model car, and directly drives the two front wheels and the two rear wheels, respectively.

TECHNICAL FIELD OF THE INVENTION

The present invention generally relates to model cars, and moreparticularly to a model car having a four-wheel driving system.

DESCRIPTION OF THE PRIOR ART

Existing remote-control model cars have their rear wheels driven by aminiature gasoline engine. The front wheels on the other hand areconnected to the steering mechanism of the model car for directioncontrol. These remote-control model cars are simple to manufacture andoperate rather smoothly over flat surfaces. However, for bumpy or steepsurfaces, their performance and reliability are less than satisfactory.In addition, these rear-wheel driven model cars are slower and moredifficult to control.

SUMMARY OF THE INVENTION

As such, a four-wheel drive model car is provided herein to overcome thedisadvantages of the prior arts.

According to the present invention, a miniature gasoline engine isinstalled at the rear section of the model car, which provides areasonable center of gravity to the model car and therefore a reliableoperation. The transmission assembly is configured such that the maintransmission axle runs axially through the model car and directly drivesthe two front wheels and the two rear wheels, respectively, through thecouplings, front and rear differentials, and the suspension systems.

A first transmission gear is connected to and driven by the axle of theminiature gasoline engine, which in turn engages a parallel, secondtransmission gear, which is mounted at an end of a first transmissionaxle. A first bevel gear is provided at the other end of the firsttransmission axle, which engages a perpendicular, second bevel gear. Thesecond bevel gear is connected to a center differential located in thecenter of the model car which in turn drives a second transmission axle(i.e., the main transmission axle) running through the centerdifferential.

The foregoing object and summary provide only a brief introduction tothe present invention. To fully appreciate these and other objects ofthe present invention as well as the invention itself, all of which willbecome apparent to those skilled in the art, the following detaileddescription of the invention and the claims should be read inconjunction with the accompanying drawings. Throughout the specificationand drawings identical reference numerals refer to identical or similarparts.

Many other advantages and features of the present invention will becomemanifest to those versed in the art upon making reference to thedetailed description and the accompanying sheets of drawings in which apreferred structural embodiment incorporating the principles of thepresent invention is shown by way of illustrative example.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic diagram showing the transmission assembly of afour-wheel drive model car of the present invention.

FIG. 2 is a top view showing the model car equipped with thetransmission assembly of FIG. 1.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The following descriptions are exemplary embodiments only, and are notintended to limit the scope, applicability or configuration of theinvention in any way. Rather, the following description provides aconvenient illustration for implementing exemplary embodiments of theinvention. Various changes to the described embodiments may be made inthe function and arrangement of the elements described without departingfrom the scope of the invention as set forth in the appended claims.

FIG. 1 is a schematic diagram showing the transmission assembly of afour-wheel drive model car of the present invention. A firsttransmission gear 1 shown in the diagram is connected to and driven bythe axle of a miniature gasoline engine (not shown). The transmissiongear 1 in turn engages a parallel, second transmission gear 2 which ismounted at an end of a first transmission axle (not numbered) for speedreduction. A first bevel gear 3 is provided at the other end of thefirst transmission axle, which engages a perpendicular, second bevelgear 4. The second bevel gear 4 is connected to a center differential(not numbered) which in turn drives a second transmission axle 5 whichruns through the center differential. The two ends of the secondtransmission axle 5 then drive the two front wheels and the two rearwheels, respectively, through the couplings, front and reardifferentials, and the suspension systems.

FIG. 2 is a top view showing the model car equipped with thetransmission assembly of FIG. 1, which is located at where the circle Ais marked. The miniature gasoline engine is installed at the rearsection of the model car, which provides a reasonable center of gravityto the model car. The transmission assembly of FIG. 1 is configured suchthat the second transmission axle 5 runs axially through the model carand the center differential is in the center of the model car.

The configuration of the miniature gasoline engine and the transmissionassembly provide a highly reliable operation to the model car overvarious types of terrains. In addition, the axially aligned secondtransmission axle provides powerful and highly efficient driving to thefour wheels so that the model car can run at great speeds with superiormaneuverability.

It will be understood that each of the elements described above, or twoor more together may also find a useful application in other types ofmethods differing from the type described above.

While certain novel features of this invention have been shown anddescribed and are pointed out in the annexed claim, it is not intendedto be limited to the details above, since it will be understood thatvarious omissions, modifications, substitutions and changes in the formsand details of the device illustrated and in its operation can be madeby those skilled in the art without departing in any way from the spiritof the present invention.

1. A four-wheel drive model car having a gasoline engine, two frontwheels, two rear wheels, a center differential, a front differentdifferential, a back differential, a front suspension system, a backsuspension system, a front coupling, and a back coupling, comprising: afirst transmission gear connected to and driven by the axle of saidgasoline engine installed at the rear section of said model car; a firsttransmission axle; a parallel, second transmission gear at an end ofsaid first transmission axle and engaged by said first transmissiongear; a first bevel gear at the other end of said first transmissionaxle; a second bevel gear engaged by said first bevel gear and connectedto said center differential; and a second transmission axle driven bysaid center differential running axially through said model car, the twoends of said second transmission axle driving said two front wheels andsaid two rear wheels, respectively, through said front and rearcouplings, differentials, and suspension systems of said model car. 2.The four-wheel drive model car according to claim 1, wherein said firstbevel gear and said second bevel gear are perpendicular.
 3. Thefour-wheel drive model car according to claim 1, wherein said firsttransmission gear and said second transmission gear are engaged forspeed reduction.
 4. The four-wheel drive model car according to claim 1,wherein said center differential is located in the center of said modelcar.